Usiah Selemale and Immanuel Selema put up perches for birds in the introduction unit.

Top level of the walkthrough aviary overlooking the city as it looked like in 2004.

The NZG's walkthrough aviary is one of the largest in Africa -- about 75m long, 33m wide and 23m high (estimated at seven storeys).

The aviary was constructed in 2001 on a slope along the Apies River overlooking the city. The first group of African and exotic birds was released into the aviary in December 2004.

At the beginning of 2011 it had become clear that the 10-year-old structure needed a facelift. The NZG bird keepers decided to make use of the opportunity to select material that was more eco-friendly and durable to ensure the safety of the birds as well as the public. Maintenance included repainting the steel poles and replacing wooden walkways and wire mesh.

Upgrading the aviary

Birds were captured and moved out of the aviary between February and March 2011 to ensure their safety. Wooden walkways were replaced with durable non-slip and water-resistant ones made of pvc and wood chips. Stairways were replaced on the eastern side as well as the wooden bridge over the wetland. The rusting wire mesh was replaced with stainless steel netting wire mesh. The beam and other steel poles were sanded and repainted. Coconut ropes used as a barrier along the walkway to the bridge were replaced with steel cable covered with plastic pipe. Transparent plastic curtains were put up at the entrances to prevent birds from escaping when public enter the aviary. The introduction unit was also reinforced.

Populating the aviary

The aviary originally contained about 60% indigenous plants and 40% exotic plants to cater for African and non-African bird species. The exotic plants will now all be replaced with indigenous plant species. The process will unfold gradually as the keepers do not want to uproot or remove all vegetation at once as it might result in soil erosion. The aviary will also gradually be repopulated with African bird species.

Phase1 of the project includes the compilation of desired bird species and obtaining a list of accredited suppliers and quotations. A list of available birds from the main collection has been compiled as well as an action plan to introduce new species. A final inspection will be carried out to check that the aviary is safe and secure prior to releasing the birds back into it.

In Phase 2 of the project, the available birds will be placed in the introduction unit for two to three weeks to make sure that they are adapting or acclimatising to the environment, and eating well, before the gate leading to the big aviary is opened to let them through.

Zoo e-News readers are invited to visit the new-look aviary on their next visit to the Zoo.

Keep an eye on our Facebook page for regular updates on the opening date of our magnificent walkthrough aviary.

By Sarah Chabangu and Lehlogonolo Leshaba, NZG

The National Zoological Gardens of
South Africa is a proud facility of
the National Research Foundation